Cisco Systems 78-11741-02 manual Igmp Proxy, IPC-507

Configuring Unidirectional Link Routing

UDLR Overview

In a large enterprise network, it is not possible to be able to receive IP multicast traffic via satellite and forward the traffic throughout the network. This limitation exists because receiving hosts must be directly connected to the downstream router. However, you can use the IGMP Proxy mechanism to overcome this limitation. See the “IGMP Proxy” section later in this chapter for more information on this mechanism.

For information on IGMP, refer to the “Configuring IP Multicast Routing” chapter in the Cisco IOS IP Configuration Guide.

IGMP Proxy

The IGMP Proxy mechanism enables hosts that are not directly connected to a downstream router to join a multicast group sourced from an upstream network. Figure 82 illustrates this mechanism.

Figure 82 IGMP Mroute Proxy Mechanism

	Unidirectional	Router A
	tunnel
Internet		Unidirectional link
		Router B
LAN B		RP
		Local net
		Router C
		User 1
		46457

Cisco IOS IP Configuration Guide

IPC-507